You may remember my saying a while back that the oil filter is of the non replacement type – its mostly made of brass (strange that) and the inside is a thinnish wire coiled around a frame that you simply wash in petrol and put it back. The reason for this is that the older oils were very thin so any swarf or dirt etc by design dropped into the bottom of the sump. The oil filter was there merely to catch the larger pieces of debris. Modern oils however are vastly improved but they are designed to carry dirt and debris and let the oil filter catch it all. Which is why it is important to be replaced regularly because it will clog up. You may also remember my saying that when i undid the oil filter the nice neatly wound wire interior exploded into a fierce-some bids nest instead. THAT won’t be going back together i can tell you.
So what to do… i spoke to learned council and he suggested hunting for a spare at auto jumbles which is a reasonable suggestion because i want to keep as much as possible in period. However talking to a number of vintage car owners at the Brooklands Double 12 race event, they laughed and said why would you want to rely on a rubbish filtration system which is not designed for modern oils. Their advice was to machine up a convertor in order to fit a modern filter and use better oil which can only prolong the life of the engine. I had to admit both parties have a point, but i think in this instance i am going to step away from a period part and have an oil filter that actually works. Its buried low in the engine so it won’t stand out. To the machine shop…..
I have zoomed in to the original oil filter housing which is about 2.5 inches across. In the middle is the thread that the original casing used to feel oil up the centre of the filter. So i need a fairly substantial hollow rod threaded the right size and also of a suitable length that a small modern filter will then then screw onto it, plus a separate metal plate that screws into the inside rim of the housing but extends outwards producing a flat plate so that the modern filter can fit flush. Hmm… this is out of my league.
Time to call the Vintage racing boys – surely there must be someone who has made this and has the diagrams etc.
Hurrah! I have found a chap that not only knows how to make them he uses one on his own car and makes them for a renowned Riley engine builder. A friendly conversation later and he posted one to me in exchange for a few pounds. Riley people generally seem to be nice people – thank you Steve Hughes.
Here are the component parts – a central rod, the flat plate in aluminium (shame its not brass) and a jolly small oil filter.
The rod screws into the middle and it locked into place with a little thread seal.
Next the adapter plate is spun into place and locked using a C spanner – which luckily i had.
And finally the filter is spun on in the usual manner
Subtle enough and i rather suspect there are more of these conversions out there than i had ever noticed.